A bid by two men to become the first Japanese to cross the Pacific in a balloon ended Tuesday evening some 12 hours after it began.
Michio Kanda, a 54-year-old official of the municipal government of Kawajima, Saitama Prefecture, and Naoki Ishikawa, 26, a graduate student of the Tokyo National University of Fine Arts and Music, made an emergency landing in waters about 1,500 km east of Miyagi Prefecture.
Supporters said both men were uninjured.
The pair had planned to make the 8,000- to 9,000-km trip to North America in about 60 hours.
The Japan Coast Guard said it dispatched patrol ships and planes to the area to rescue the pair.
Kanda holds the world record for the longest hot-air balloon flight at 50 hours, 38 minutes.